Tacoma 2.4L 4-Cyl. Calif. Emission Vehicles, Tacoma 2.7L 4-Cyl. Calif. Emission Vehicles & 4Runner 2.7L 4-Cyl. Calif. Emission Vehicles

Distributorless Ignition System (DIS) uses Engine Control Module (ECM) for determining ignition timing (spark advance). ECM may determine ignition timing (spark advance) based on various input signals, engine RPM and knock sensor input signals.

Conventional distributor and pick-up coil have been replaced by camshaft position sensor and crankshaft position sensor. Camshaft position sensor and crankshaft position sensor deliver input signals to ECM. ECM detects standard crankshaft position based on camshaft position sensor input signals and actual crankshaft position, and engine speed by crankshaft position sensor input signals. Camshaft position sensor is located at driver's side front corner of cylinder head, just in front of intake manifold. See Figure and Figure . Crankshaft position sensor is located near crankshaft pulley, just above oil pan on driver's side of engine. See Figure and Figure . For knock sensor location, see REMOVAL, OVERHAUL & INSTALLATION - 4-CYLINDER article.

ECM uses 4 ignition primary control signals to ignitors for ignition coils. DIS uses 4 ignition coils with internal ignitors, one ignition coil for each cylinder. See Figure. Cylinder No. 1 is front cylinder at timing chain end of engine and cylinder No. 4 is rear cylinder at flywheel end of engine. ECM monitors IGF circuit at ignitor to ensure ignition coils have fired.